powernukkit / region-manipulator

A kotlin/java lib that allows you to read and write MCA files in a clean way

Region Manipulator

A Kotlin/Java library that allows you to read and write mca files in a simple way.

Here you can find the library documentation:

• Java Documentation
• Kotlin Documentation

You may also want to see the changelog file to be aware of all changes in the tool that may impact you.

Adding to your project

The library is shared in the maven center, so you don't need to declare any custom repository.

Gradle

repositories {
    mavenCentral() // or jcenter()
}

dependencies {
    compile 'br.com.gamemods:region-manipulator:2.0.0'
}

Maven

<dependencies>
    <dependency>
      <groupId>br.com.gamemods</groupId>
      <artifactId>region-manipulator</artifactId>
      <version>2.0.0</version>
    </dependency>
</dependencies>

Ivy

<dependency org="br.com.gamemods" name="region-manipulator" rev="2.0.0"/>

Direct JAR

Download it from maven central.

Examples

internal fun clearEntities(from: File, to: File) {
    val region = RegionIO.readRegion(from)
    val chunk = region[ChunkPos(region.position.xPos * 32, region.position.zPos * 32)] ?: return
    chunk.level.getCompoundList("Entities").forEach { 
        println(it.getString("id") + " "+ it.getDoubleList("Pos"))
    }
    chunk.level["Entities"] = emptyListOf<NbtCompound>().toNbtList()
    RegionIO.writeRegion(to, region)
}

region-manipulator's Issues

kotlin.KotlinNullPointerException when reading a region file

That's why we should never use !!.

kotlin.KotlinNullPointerException
	at br.com.gamemods.regionmanipulator.RegionIO.readRegion(RegionIO.kt:47)
	at br.com.gamemods.regionmanipulator.RegionIO.readRegion(RegionIO.kt:26)
	at br.com.gamemods.j2nwc.internal.RegionFileConverter.convertRegionFile(RegionFileConverter.kt:18)
	at br.com.gamemods.j2nwc.WorldConverter.convert(WorldConverter.kt:101)
	at br.com.gamemods.worldrepo.MundoJava.converterParaNukkit(MundoJava.kt:29)
	at br.com.gamemods.worldrepo.MundoConstrucao.publicar(MundoConstrucao.kt:181)
	at br.com.gamemods.worldrepo.ImportadorDeMundo$Companion.importarLegado(ImportadorDeMundo.kt:104)
	at privado.Importar_legadoKt.main(importar-legado.kt:16)
	at privado.Importar_legadoKt.main(importar-legado.kt)

The failing region file:
r.0.-1.mca.zip

IndexOutOfBoundsException when writing an empty chunk

java.lang.IndexOutOfBoundsException
	at java.nio.ByteBuffer.wrap(ByteBuffer.java:375)
	at br.com.gamemods.regionmanipulator.RegionIO.writeRegion(RegionIO.kt:133)
	at br.com.gamemods.regionmanipulator.RegionTest.testReadMCA1(RegionTest.kt:18)

Corrupt chunk prevents the entire region to load

java.io.UTFDataFormatException: malformed input around byte 1
	at java.io.DataInputStream.readUTF(DataInputStream.java:656)
	at java.io.DataInputStream.readUTF(DataInputStream.java:564)
	at br.com.gamemods.nbtmanipulator.NbtCompoundSerial.readTag(NbtIO.kt:244)
	at br.com.gamemods.nbtmanipulator.NbtCompoundSerial.readTag(NbtIO.kt:235)
	at br.com.gamemods.nbtmanipulator.NbtListSerial.readTag(NbtIO.kt:213)
	at br.com.gamemods.nbtmanipulator.NbtListSerial.readTag(NbtIO.kt:203)
	at br.com.gamemods.nbtmanipulator.NbtCompoundSerial.readTag(NbtIO.kt:246)
	at br.com.gamemods.nbtmanipulator.NbtCompoundSerial.readTag(NbtIO.kt:235)
	at br.com.gamemods.nbtmanipulator.NbtCompoundSerial.readTag(NbtIO.kt:246)
	at br.com.gamemods.nbtmanipulator.NbtCompoundSerial.readTag(NbtIO.kt:235)
	at br.com.gamemods.nbtmanipulator.NbtIO.readNbtFile(NbtIO.kt:65)
	at br.com.gamemods.regionmanipulator.RegionIO.readRegion(RegionIO.kt:69)
	at br.com.gamemods.regionmanipulator.RegionIO.readRegion(RegionIO.kt:26)
	at br.com.gamemods.j2nwc.internal.RegionFileConverter.convertRegionFile(RegionFileConverter.kt:18)
	at br.com.gamemods.j2nwc.WorldConverter.convert(WorldConverter.kt:101)
	at br.com.gamemods.worldrepo.MundoJava.converterParaNukkit(MundoJava.kt:29)
	at br.com.gamemods.worldrepo.MundoConstrucao.publicar(MundoConstrucao.kt:181)
	at br.com.gamemods.worldrepo.ImportadorDeMundo$Companion.importarLegado(ImportadorDeMundo.kt:104)
	at privado.Importar_legadoKt.main(importar-legado.kt:16)
	at privado.Importar_legadoKt.main(importar-legado.kt)

Should allow to load the region but without the corrupted chunk.

The failing region file:
r.-1.-1.mca.zip

Proof that it is corrupted:

Error upgrading chunk [-24, -17]
java.io.UTFDataFormatException: malformed input around byte 1
	at java.io.DataInputStream.readUTF(DataInputStream.java:656) ~[?:1.8.0_201]
	at java.io.DataInputStream.readUTF(DataInputStream.java:564) ~[?:1.8.0_201]
	at net.minecraft.server.v1_14_R1.NBTTagCompound.b(SourceFile:431) ~[spigot-1.14.2-R0.1-SNAPSHOT.jar:git-Spigot-093165d-cb3d14c]
	at net.minecraft.server.v1_14_R1.NBTTagCompound.load(SourceFile:78) ~[spigot-1.14.2-R0.1-SNAPSHOT.jar:git-Spigot-093165d-cb3d14c]
	at net.minecraft.server.v1_14_R1.NBTTagList.load(SourceFile:65) ~[spigot-1.14.2-R0.1-SNAPSHOT.jar:git-Spigot-093165d-cb3d14c]
	at net.minecraft.server.v1_14_R1.NBTTagCompound.a(SourceFile:438) ~[spigot-1.14.2-R0.1-SNAPSHOT.jar:git-Spigot-093165d-cb3d14c]
	at net.minecraft.server.v1_14_R1.NBTTagCompound.load(SourceFile:81) ~[spigot-1.14.2-R0.1-SNAPSHOT.jar:git-Spigot-093165d-cb3d14c]
	at net.minecraft.server.v1_14_R1.NBTTagCompound.a(SourceFile:438) ~[spigot-1.14.2-R0.1-SNAPSHOT.jar:git-Spigot-093165d-cb3d14c]
	at net.minecraft.server.v1_14_R1.NBTTagCompound.load(SourceFile:81) ~[spigot-1.14.2-R0.1-SNAPSHOT.jar:git-Spigot-093165d-cb3d14c]
	at net.minecraft.server.v1_14_R1.NBTCompressedStreamTools.a(NBTCompressedStreamTools.java:114) ~[spigot-1.14.2-R0.1-SNAPSHOT.jar:git-Spigot-093165d-cb3d14c]
	at net.minecraft.server.v1_14_R1.NBTCompressedStreamTools.a(NBTCompressedStreamTools.java:83) ~[spigot-1.14.2-R0.1-SNAPSHOT.jar:git-Spigot-093165d-cb3d14c]
	at net.minecraft.server.v1_14_R1.NBTCompressedStreamTools.a(NBTCompressedStreamTools.java:73) ~[spigot-1.14.2-R0.1-SNAPSHOT.jar:git-Spigot-093165d-cb3d14c]
	at net.minecraft.server.v1_14_R1.RegionFileCache.read(RegionFileCache.java:55) ~[spigot-1.14.2-R0.1-SNAPSHOT.jar:git-Spigot-093165d-cb3d14c]
	at net.minecraft.server.v1_14_R1.WorldUpgrader.i(WorldUpgrader.java:120) ~[spigot-1.14.2-R0.1-SNAPSHOT.jar:git-Spigot-093165d-cb3d14c]
	at java.lang.Thread.run(Thread.java:748) [?:1.8.0_201]

Removing existing chunks from region throws server errors when loaded.

After removing a bunch of chunks from a region folder, I receive errors like this the next time the server starts up:

[01:43:06] [chunk IO worker/WARN]: Chunk [-8, -21] is allocated, but stream is missing
[01:43:06] [chunk IO worker/WARN]: Chunk [-7, -21] is allocated, but stream is missing
[01:43:06] [chunk IO worker/WARN]: Chunk [-6, -21] is allocated, but stream is missing
[01:44:38] [chunk IO worker/ERROR]: Chunk [-11, -26] header is truncated: expected 8192 but read 0
[01:44:38] [Server thread/ERROR]: Chunk file at [-9, -26] is in the wrong location; relocating. (Expected [-9, -26], got [-3, -6])
[01:44:38] [Server thread/WARN]: Found invalid structure reference [ Mineshaft @ [2, -4] ] for chunk [-9, -26].
[01:44:38] [chunk IO worker/WARN]: Chunk [-8, -26] is allocated, but stream is missing
[01:44:38] [chunk IO worker/WARN]: Chunk has both internal and external streams
[01:44:38] [chunk IO worker/ERROR]: External chunk path .\world\region\c.-5.-26.mcc is not file
[01:44:38] [chunk IO worker/ERROR]: Chunk [-4, -26] header is truncated: expected 8192 but read 0
[01:44:38] [chunk IO worker/WARN]: Chunk [-3, -26] is allocated, but stream is missing
`

Basically, you should be able to remove almost all of a chunks in a region to recreate the issue. Here's a copy of the region files that gets corrupted:
r.-1.-1.zip

Corrupt Chunks Handling

There seem to be a lot of false-positives as far as corrupt chunks go. I can't really make a proper bug report since I can't read kotlin, but I seem to get a lot of instances where perfectly normal chunks are marked as corrupt.

Issue reading 1.15 region.

Hello,

I've been using this util in one of my plugins, and while updating my server to 1.15, I started receiving the following error: `

[21:25:55] [Server thread/WARN]: java.io.EOFException
[21:25:55] [Server thread/WARN]: at java.base/java.io.RandomAccessFile.readFully(Unknown Source)
[21:25:55] [Server thread/WARN]: at java.base/java.io.RandomAccessFile.readFully(Unknown Source)
[21:25:55] [Server thread/WARN]: at br.com.gamemods.regionmanipulator.RegionIO.readRegion(RegionIO.kt:63)
[21:25:55] [Server thread/WARN]: at br.com.gamemods.regionmanipulator.RegionIO.readRegion(RegionIO.kt:26)
[21:25:55] [Server thread/WARN]: at me.zombie_striker.chunkculler.Main.cullForWorld(Main.java:666)
[21:25:55] [Server thread/WARN]: at me.zombie_striker.chunkculler.Main.cullForWorld(Main.java:599)
[21:25:55] [Server thread/WARN]: at me.zombie_striker.chunkculler.Main.onDisable(Main.java:329)
[21:25:55] [Server thread/WARN]: at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:265)
[21:25:55] [Server thread/WARN]: at org.bukkit.plugin.java.JavaPluginLoader.disablePlugin(JavaPluginLoader.java:377)
[21:25:55] [Server thread/WARN]: at org.bukkit.plugin.SimplePluginManager.disablePlugin(SimplePluginManager.java:438)
[21:25:55] [Server thread/WARN]: at org.bukkit.plugin.SimplePluginManager.disablePlugins(SimplePluginManager.java:430)
[21:25:55] [Server thread/WARN]: at org.bukkit.craftbukkit.v1_15_R1.CraftServer.disablePlugins(CraftServer.java:396)
[21:25:55] [Server thread/WARN]: at net.minecraft.server.v1_15_R1.MinecraftServer.stop(MinecraftServer.java:698)
[21:25:55] [Server thread/WARN]: at net.minecraft.server.v1_15_R1.DedicatedServer.stop(DedicatedServer.java:683)
[21:25:55] [Server thread/WARN]: at net.minecraft.server.v1_15_R1.MinecraftServer.run(MinecraftServer.java:863)
[21:25:55] [Server thread/WARN]: at java.base/java.lang.Thread.run(Unknown Source)

My plugin worked on 1.14, and now this error appears whenever my plugin tries to read any chunk from my 1.15 world.